LOUISVILLE – Everyone knows the Kentucky Derby is America’s greatest horse race, but they may not even be half-right. The real story of the Kentucky Derby is that it is a trainer’s race.

And if anyone had any doubt, they had only to stare, almost in disbelief, as the field of 18 horses thundered down the stretch yesterday for the 128th running of the Derby. There, at the head, leading the thrilling charge, were two horses, totally discarded by the betting and handicapping public as of little consequence.

All they had going for them were their trainers – two of the giants of the American turf, two titans who train winner after winner in the nation’s classics. Bob Baffert and Wayne Lukas.

Incredible. Both their horses, the winner War Emblem, and the gutsy second, Proud Citizen, rocked the tote board at 20-1 each. This, I say, could never happen anywhere else. Only in America does the betting community give the raspberry to trainers who, year after year, dominate the Triple Crown.

The Derby is a trainer’s race all right, but don’t let anyone suggest it is a jockey’s race. How any reasonably astute bunch of jockeys could allow relative newcomer Victor Espinoza, riding only his second Derby, to sit on a lead and crawl through the early fractions without once offering any pressure is beyond me.

This Derby was supposed to be a speed battle, set up for closers. What a joke! Robby Albarado on Request for Parole, Laffit Pincay Jr. on Medaglia d’Oro, and Chris McCarron on Came Home handed the race to the winner.

At no stage of the mile-and-a-quarter did they push. So they allowed Espinoza to jog through unbelievably slow fractions. Then, when they tried to go after War Emblem, Espinoza just said to the leader, “Let’s go,” and he drew off like an express train to win by four lengths.

Not since Winning Colors won the Derby in 1988 has a horse won wire-to-wire as War Emblem did yesterday.

Any chance the favored closers had of winning the race were scuttled when War Emblem coasted. At the finish, they had nothing to run at. So the heavily bet Saarland, Essence of Dubai, Blue Burner, Lusty Latin, Harlan’s Holiday, Castle Gandolfo and Johannesburg just plodded home.

The only stretch runner who unfurled a terrific performance was Perfect Drift, who finished third.

The result was a stunning reminder of the tricky speed-figure business. War Emblem went into the Derby with a Beyer 112, eight points better than any other runner. Yet not one speed-figure handicapper picked him to win – as was foretold in this column last week.

War Emblem was bought for a reported $1 million by the Thoroughbred Corp., a group of Saudi Arabian businessmen headed by Prince Ahmed Salman, after he won the Illinois Derby a month ago.

He was given to Baffert to prepare for the Derby by the prince, who last year suffered a huge disappointment when his Point Given finished off the board as the Derby favorite.

After War Emblem’s victory, the Saudi tycoon cried, “Winning the Kentucky Derby has always been my dream. I would like to thank Bob Baffert, he is a genius.”

Six weeks ago, the silver-haired trainer had nothing in his barn for the Derby. Then out of the blue, here comes War Emblem. Said Baffert, “We came in here through the back door but we are leaving through the front door.”

He’s lucky he wasn’t booted out the front door. He turned the Derby draw into consternation when he unexpectedly entered Danthebluegrassman at the last moment and forced Windward Passage out of a starting berth. Then, on Derby morning, Dan had to be scratched because of a minor health problem.

But in the wash-up, it made no difference. No one was going to beat War Emblem on the easy pace.

At a press conference after the race, Prince Salman was asked about winning the Derby in the aftermath of Sept. 11 and the role Saudis may have played in the treacherous assault.

“I am a businessman, not a politician,” said the prince. “I leave all that to the politicians.”

When asked if he had “bought” the Derby by buying War Emblem just before the race, he exploded, “Everybody buys the Derby. No matter where or how you get the horse, you buy it.”

Baffert chimed in, “Anybody who says that is just jealous.”

The Derby outcome was a great boost for the Australian betting system, frequently mentioned in these columns over the years. It says: big race, big trainer, big odds, big bet.

So here were Baffert, Lukas and Bill Mott, three of the greatest trainers in the world, sending out horses at 20-1, 20-1 and 24-1 and among them they set up a $1,300 exacta. Only a dummy (like me) would bet the winner and second and skip the exotic.

Not much can be said for the Derby flops. Saarland never got into it. Came Home and Harlan’s Holiday ran like tired horses. Johannesburg got the run of the race along the rail but never looked like winning. The Dubai connection crashed badly with Essence of Dubai, which they touted as their best shot yet, while Blue Burner, from the extreme outside, never got into the mix.

Pace, they say, makes the race, and this Derby wrote it in neon. A quality speed horse, allowed to float in front, is almost impossible to catch. If they let him do it in the Preakness in two weeks, War Emblem will breeze again.